fall flat

Verb

fall flat (third-person singular simple present falls flat, present participle falling flat, simple past fell flat, past participle fallen flat)

1. To produce no humour, inspiration, etc.
   • The prop comedy in Las Vegas fell flat.
   • When Sir Walter Scott, with a view to profit rather than fame, published "Paul's Letters to his Kinsfolk," with some very indifferent verses to celebrate the battle of Waterloo, Erskine, sitting at table, came out with the following impromptu:—1847, John Campbell, 1st Baron Campbell, The Lives of the Lord Chancellors and Keepers of the Great Seal of England, volume VI, page 518